Apparatus for configurating paper blanks



.lO Sheets-Sheet l INVENTOR.

APPARATUS FOR CONFIGURATING PAPER BLNKS /m/ENTOR.

Feb- 28, i967 c. EDWARDS 3,3%,145

APPARATUS FOR CONFIGURATING PAPER BLANKS Filed Sept. 8, 1964 10 Sheets-Sheet 5 f, l 3 "'46 /0/ j /z l 93 1 l NW g y@ W 37 45 44 O O 0 O O C O O O O O O O O O O 0 O VENTOR.

Feb, 28, E967 c. L.. EDWARDS APPARATUS FOR CONFIGURATING PAPER BLNKS Filed Sept. 8, 1964 A@Lf/,77/

l0 Sheets-Sheet 6 Kyiv INVENTOR ,W'/F//ff J Fa. 28, 1967 c. L. 5mm/mns APPARATUS FOR CONFIGURATING PAPER BLANKS 10 Sheets-Sheet '7 Filed Sept. 8, 1964 Feb. 28, 1967 c. 1 EDWARDS 393%5 APPARATUS FOR CONFIGURATING PAPER BLANKS Filed Sept. 8, 1964 l0 Sheets-Sheet 8 780 INVENTOR.

.r F9 l Feb Z, 395? c. L. EDWARDS APPHTUS FOR GONFGURATING PAPER BLANKS l@ Sheets-Sheet 9 Filed sept. s, 1964 INVENTOR. 5;; /Cf

Reb 23, 3%? c. a.. Erm/Amas ppm APPARATUS FDR CONFIGURATING PAPER BLANKS Filed sept. e, 1964 l0 SheetsmSheet l0 United States Patent Ciiiice 3,3%,145 Patented Feb. 28, 1967- 3,306,145 APPARATUS FR CNFIGURATING PAPER BLANKS Carl L. Edwards, Reading, Ohio, assigner to Multi- Colortype Co., Cincinnati, Ohio, a corporation of Ghio Filed Sept. S, 1964, Ser. No. 394,921 8 Claims. (Ci. 83-157) The invention relates to apparatus for trimming paper blanks and more particularly the invention is directed to apparatus for die cutting a particular configuration in at least one edge of a stack of paper blanks.

It has been possible to cut a stack of paper blanks to a particular size and configuration by forcing the stack through a hollow die having the desired configuration. In trimming by ramming a stack through a hollow die, it is necessary for the stack to be engaged by the hollow die on all four sides so that the pressure of the die on the stack is uniformly applied to the stack. If it were otherwise, that is, it the cutting die engaged less than four sides, the imbalance of pressures applied to the stack would cause the sheets in it to cant with respect to their direction of movement and to be non-uniformly cut. A lack of uniformity in the cutting would be particularly disadvantageous in the case of such items as labels or wrappers which must be fed through high speed packaging machines.

It can be seen, therefore, that to use hollow die type machines of known design for trimming sheet stacks, it is necessary to feed into the machine sheets which are cut slightly over-size all around their peripheries so that they can be engaged around their peripheries by the knife edge of the hollow die. Perhaps an eighth to a quarter of an inch must be trimmed from around the periphery of the stack. In a highly competitive business such as the manufacture of printed wrappers for cigarette packages, for example, loss must be kept to an absolute minimum. To lose an eighth to a quarter of an inch around the periphery of each sheet, would be suicidal from a cornpetitive standpoint.

The principal objective of the present invention has been to provide die cutting apparatus by which less than the complete periphery and preferably one edge of a stack can be cut to a desired configuration without requiring any waste paper around the other edges. This objective econtemplates the provision of apparatus for receiving a stack of sheets and for clamping that stack so securely as to eliminate any possibility of the stack or sheets in the stack becoming canted when the stack is engaged by the cutting die.

It is not enough merely to clamp a stack of sheets perpendicularly to the plane of the sheets between two jaws during the cutting operation. If the sheets are slightly misaligned, prior to clamping, the precise trimming of one edge of the stack will result in sheets which have a variation in size and relative position of the configuration imparted to them by the trimming, the magnitude of the variations depending upon the magnitude of the misalignment prior to the clamping.

It has, therefore, been another objective of the invention to provide aligning means which engage the four sides of the stack, on the sheet edges, first to bring the stack into proper alignment and to hold or clamp the stack securely in alignment prior to the application of the main clamp to the stack.

It has been another objective of the invention to provide apparatus of the type described above wherein stacks of sheets may -be loaded into a conveyor and thereafter automatically conveyed into the cutting apparatus to be aligned, clamped and cut and thereafter discharged automatically and in timed sequence.

It has been another objective of the invention is provide means for aligning and clamping two opposed faces of the stack with the same power mechanism which applies the main clamping pressure to the stack.

It has been another objective of the invention to provide a conveyor for moving stacks into the cutting mechanism, the conveyor also providing a plate and pressure on the plate for effecting the alignment and of two opposed faces of the stack.

It has been another objective of the invention to provide apparatus of the type described in which a table surface and back-wall are inclined to provide a V-cradle for supporting stacks which are conveyed to the cutting die.

These and other objectives of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of the apparatus constructed in accordance with the invention,

FIG. 2 is a front elevational view thereof,

FIG. 3 is a cross sectional view taken along lines 3 3 of FIG. 2,

FIG. 4 is a cross sectional view taken along lines 4 4 of FIG. 2,

FIG. 5 is a cross sectional view taken along lines 4 4 of FIG. 2, showing a stack fully clamped but as yet uncut,

FIG. 6 is a cross sectional view taken along lines 6 5 of FIG. 5,

FIG. 7 is a fragmentary view, partly in section, illustrating the cutting knife and the stop which limits its downward movement,

FIG. 8 is a cross sectional view taken along lines 8 8 of FIG. 7,

FIG. 9 is a fragmentary front elevational view of the cutting die and the movable wall portion in which it is mounted,

FIG. 10 is a cross sectional view taken along lines 1% 16 of FIG. 9,

FIGS. 11, 13, l5, 17, 19, 21, and 23 are perspective views illustrating the sequence of operations of the respective elements of the invention, and FIGS. 12, 14, 16, 18, 20, 22, and 24 are cam positions illustrating the operation of the micro-switches which control the movement apparatus elements illustrated in FIGS. 11-23 respectively, and

FIGS. 25-26 are circuit diagrams of the apparatus.

General organization The operating mechanism of the invention is supported on a table 29 having top 30 providing a downwardly and rearwardly inclined conveyor surface 31 `ou which stacks 32 of sheets to be cut are mounted. The table 29 includes a pair of legs 33 and 34 between which most of the drive system for the invention is mounted as well as a cam and micno-switch system 35 which is employed to properly program the sequence of operations.

Mounted above the table surface 31 is a superstructure 36 including a pair of uprights 37 and 38, the legs 37 and 38 support a plate 39 on which are mounted a clamping ram 40 and a cutting ram 41, both of which are pneumatically operated. A wall 42 projects perpendicularly from the table surface 31 to provide, with the surface 31, a V-guide -for the stacks of paper as they are conveyed to cutting position.

The table surface is inclined approximately 30 to horizontal, and as a consequence, most of the principal elements are inclined so las to be mounted and to yoperate either perpendicularly or parallel to the table. For the sake of clarity in certain instances, reference will be made to horizontal and Vertical elements and movements, it be ing understood that the elements and movements will be at a slight angle to the vertical.

The table has a channel or groove 44 which receives and supports an endless chain conveyor 45 which carries upstanding lugs 46 that engage the stacks 32 to move them into the clamping and cutting mechanism supported by the super-structure.

The stacks are clamped :on all six sides between three pairs of aligning or clamping elements. The first pair of clamping elements may be termed the longitudinal clamp and is constituted by the lug 46 of the conveyor 45 on one side and a longitudinal clamping plate 50 on the other side. The plate 50 is transversely movable into and out of clamping position by means of a pneumatic ram 51. The longitudinal clamp is the first to engage the stack in the sequence of operation.

A transverse clamp is constituted by the back-wall 52 which projects perpendicularly upwardly from the table surface 31. As will Ibe explained below, that wall 52 is movable downwardly with the cutting die, but during the clamping sequence it is in a position to engage one side of the stack to be clamped. The other transverse clamping member is -a plate 53 which is slidably mounted on the table and is driven into clamping engagement with the stack by a vertically movable roller 55 which engages a cam surface 56 on the plate 53. The roller 5S is carried by a downwardly movable plate 57, which is actuated by the clamping ram 40.

The plate 57 has a rearward extension 58 (FIG. 3) from which a clamping block 59 depends, the block forming one element of a vertical clamping pair. The other element of the vertical clamping pair is the surface 31 of the table. The transverse clamp and the vertical clamp are operated by the same clamping cylinder 40 which drives the plate 57.

As viewed in FIG. 3, a cutting die 63 is mounted on a vertical movable plate 64 which is operably connected to the cutting ram 41. The cutting die has a knife edge 65 shaped to the configuration -which is to be cut into the stack of sheets. The plate `64 also carries the wall 52 so that as the knife is driven through the stack, the wall 52 slides downwardly with the cutting die 63.

The conveyor and the timing cam 35 are driven by a motor 66. The pneumatic cylinders 40, 41 and 51 are driven by a source of compressed air indicated at 67, the compressed air being controlled -by a regulatory system indicated at 68 (FIG. 1). The feeding of the compressed air to the respective rams to control their movements to and from operative position is controlled 'by a series of limit switches operated by the timing cam 35. The initiation of the operation of the timing cam limit switches is controlled by la main limit switch LS-M having an operating arm 70 which projects upwardly from the surface 31 of the table and is engaged yby an incoming stack of papers t-o actuate the limit switch.

In brief, the operation is as follows: The operator loads stacks of paper on the table top 30 in position to be engaged by a lug 46. The conveyor intermittently moves a stack into a position adjacent and below the cutting die 63. In moving into that position, the limit switch LS- M is tripped thereby initiating the operation of the limit switches associated with the cam system 35. All of those limit switches cause the longitudinal clamping plate 50 to move transversely into the path of the incoming stack 32 whereupon it is set or aligned and clamped vbetween the plate 50 and the lug 46.

The conveyor then trips a switch which stops the conveyor. The cam system operates another limit switch to cause the vertical clamping plate and the transverse clamping plate to move into engagement with the stack. When the stack has been thus aligned and clamped, on all six sides, the cam system initiates the operation of still another limit switch which causes the cutting die to move through the edge portion of the stack to cut it to the de- 4 sired configuration. The details of the respective mechanisms participating in that operation will be described in greater detail below.

The conveyor' and longitudinal clamp Referring to FIGS. 1 to 3, the conveyor for the stacks of paper includes the endless chain 45 riding in channel 44 in the table top 30. The chain passes around idler sprocket and drive sprocket 81. The idler sprocket is mounted on a rotatable shaft 82 which is concealed behind shroud 83. Drive sprocket 81 is mounted on a shaft 84 and is fixed to the driven member of a clutch and brake 85. The driving member of the clutch and brake 85 is connected to a shaft 86 which is fixed to a sprocket 87 driven by a chain 88 connected to the motor 66, by a sprocket 89. The clutch and brake 85 has two conditions. In one, the clutch is energized and the brake is de-energized, thereby causing the conveyor chain to be driven carrying stacks into the clamping and cutting apparatus. In the other condition, the brake is energized and the clutch is de-energized to effect the longitudinal clamping of the stack, this position being held until the cutting operation has been completed. Two switches are required to effect the two operations. The energization of the `brake and de-energization of the clutch is effected by a limit switch LS-CB having an operating arm 91 engaged by the lug 46 fixed to the conveyor chain. That limit switch is best illustrated in FIG. 2 and is mounted at the left side of the apparatus as viewed in FIG. 2. By utilizing the lug 46 on the conveyor chain to initiate the braking of the conveyor chain, the conveyor chain will always stop at precisely the proper position insofar as the movement of a stack into cutting position is concerned, assuming a completely uniform spacing of the lugs 46 along the length of the conveyor chain.

The de-energization of the brake and re-energization of the clutch to cause the driving of the conveyor is effected by a limit switch LSCD which is fixed on a plate 93 and has an arm 94 engageable -by one of the cam discs in the cam and switch system 35.

The clutch permits a slight amount of slippage between -the driving and driven member which assists in effecting the longitudinal alignment and clamping of the stack of papers. Cooperating with the slippage built into the clutch and brake 85 is a special lug structure 46, as best shown in FIG. 6. That structure is constituted by an arm 95 which is fixed to the conveyor chain 45, the arm having holes through which a pair of studs 96 may pass. The studs are fixed to and project from an abutment plate 97 which is urged away from the arm 95 by a pair of compression springs 98 mounted on the studs.

When Ithe lug 46 carries a stack of papers into a cutting position, the downstream surface of the stack will engage the transverse clamping plate 50. After contact is made, the conveyor continues to move a short distance, bringing the arm 95 closer to the plate 97 against the action of the compression springs 98. When the stack is clamped quite tightly between the plates 50 and 97, the limit switch LS-CB will be tripped to de-energize the clutch and opera-te the brake. The slippage of the clutch permits the application of pressure to the stack without imparting such an overload to the motor as might cause the motor circuit to open due to overload.

The clamping plate 50 at the downstream end of the longitudinal clamp is fixed to a transversely slidable generally horizontal carriage plate 100 (FIG. 6) having a dove-tail recess 101 in its lower surface which cooperates with a dove-tail way 102 having a matching configuration, the way 102 Ibeing fixed to the table top 30. The carriage plate 100 carries a depending bracket 103 which is fixed to a rod 104 forming the movable member of the ram 51. The ram 51 is actuated to move the longitudinal clamping plate into and out of position by a limit switch LS-T actuated by the cam system 35 as will be described in greater detail below.

essaies Vertical and transverse clamps Referring generally to FIGS. 1 to 3 and specifically to FIGS. 4 and 5, when the stack 32 is clamped between the plate 50 and the lug 46, the vertical clamping block 59 moves toward engagement with the upper surface of the stack and additionally causes the transverse clamping plate 53 to move toward engagement with the stack. These movements are caused by the downward movements of the plate 57 driven by the ram 4t). The clamping plate 57 is slidably mounted on vertical ways 110 by means of bearings 111 which are xed to the plate 57. The ways are securely fixed at their lower ends to the table top and have their upper ends freely projecting above the table. A stop cylinder 112 is also xed to the top 30 of the table 29 and slidably receives a guide stud 113 fixed to the plate 57. The stop cylinder 112 and stud 113 are provided as a safety device to prevent the downward over-travel of the plate 57 which might cause damage to certain ofthe elements of the apparatus.

The plate 57 carries a downwardly depending fork 115 including a pair of legs 116 which support an axle 117 upon which the roller 55 is mounted. The roller 55 engages the cam surface 56 on the plate 53 to cause the plate 53 to move inwardly upon a downward stroke of the plate 57 which carries the roller 55 with it. The plate 53 carries rearwardly projecting posts 120 which are slidable in sleeves 121 fixed by screws 122 to a block 123, the block 123 in turn being fixed to the table 29. The posts 120 each carry a collar 124. A compression spring 125 is fixed between the collar 124 and the sleeve 121 to urge `the plate 53 outwardly away from the stack 32.

The plate 53 carries a clamping plate 128 by means of pins 129 which are fixed to the clamping plate 128 and are slidable with respect to the plate 53. Cotter pins 139 limit the slidable movement of the pins 129 with respect to the plate 53. Compression springs 131 interposed between the plates 53 and 128 urge the plate 128 away from the plate 53 and into engagement with the stack 32.

In the sequence of operations, when the ram is operated to drive the plate 57 downwardly, the engagement of the roller 55 on the cam surface 56 causes the plate 53 to move inwardly toward the stack 32. Before the downward stroke has been completed, the spring loaded plate 12S engages the surface of the stack and applies a pressure to that surface of the stack forcing it against the back-wall portion 52, that pressure increasing as the plate 53 continues its inward movement as urged by the roller 55 on the cam surface 56. That pressure tends to align the sheets in the stack and to clamp two surfaces of the stack. As the plate 53 approaches the inward extremity of its movement, the vertical damping plate 59 engages the top of the stack to apply pressure to it, clamping it against the table top 3i?.

The pressure of the plate 53 on the stack is resisted by the wall 52 at least in the ybeginning of its application. Ultimately, the pressure of the plate 53 on the stack Will be resisted by the downward clamping pressure of the plate 59 pushing the stack against the top surface 31 of the table. Further, the pressure applied by the plate 53 to the stack is suicient to move tbe stack transversely against the clamping force applied between the plate 50 and the lug on the conveyor if that is necessary for alignment purposes. The plate 53 together with the spring urged plate 128 which it carries thereby effect any transverse alignment of the sheets in the stack which may be required before the cutting die moves through the edge of the stack.

C zitting mechanism I Referring to FIGS. 3, 9, and 10, the principal element of the cutting mechanism is the cutting die 63 which is secured -by a plurality of bolts 132 to blocks 133. The blocks are in turn bolted to a plate 136 by bolts 135. Horizontal plate being secured by bolts 137 to the vertical moving plate 64. The plate 136 has longitudinal slots 138 which permit it to be adjusted so as to adjust the depth of the cut which the cutting die makes in the stack. That adjustment is made through the rotation of stop screws 139 which engage the edge of the bracket and which are mounted in a block 140 fixed to the plate 64. The plate 64 has four bearings 141 depending from it, the bearings being mounted on vertical ways 142 which are xed at their lower ends to the table 29. The plate is secured to a movable piston element 143 forming a part of the pneumatic ram 41 which drives the plate 64 and its cutting die 63 up and down.

The downward movement of the plate is limited by a pair of stops 145 located at the table top 30 on each side of the plate 64. The stop is illustrated in detail in FIG. 8. The stop is constituted by a fixed lower wedge 146 and a movable upper wedge 147 having inclined surfaces 148 and 149 respectively. A vbracket 150 is fixed to the lower wedge 146 and an adjustment screw 151 is rotatably mounted in the bracket 150 but held against axial movement by collars 152 which are fixed to the screw and are positioned on each side of the bracket 150. The screw is permitted a slight vertical movement by a slot 153 formed in the bracket 150. It can be seen that as the screw is turned, the movable wedge 147 will slide up and down the inclined surface 148 of the fixed Wedge 146 depending upon the direction of the turning of the screw thereby varying the level of the upper surface 154 of the wedge 147.

The importance of these stops can best be understood by reference to FIG. 7. In its lowermost position, as determined by the stop 145, the plate 64 carries the cutting die 63 to a position in which its knife edge 65 passes through all of the paper sheets of the stack 32 land partially through a cardboard bottom member 156. Thus, all of the sheets may be cut to the desired configuration and the dulling of the knife edge 65 will be avoided by stopping the travel of the knife edge short of the top surface 31 of the table on which the stack is mounted.

The upper edge of the wall element 52 is recessed as at 159 to accommodate the cutting die 63. Upstanding legs 157 that define this recess are bolted to the vertical legs of a pair of L-shaped brackets 158 that are secured, on each side of horizontal plate 136, to plate 64 and thus carried by the plate ahead of cutting die 63. The wall element 52 has a lower edge portion 160 which extends below the surface 31 of the table and bears against an edge surface 161, of substantial dimension (See FIG. 4). Thus the movable wall element is `braced .by the engagement of it with the brackets 158 at its upper edge and the edge 161 of the table top 36 at its lower edge portion so that it can withstand the clamping pressure applied to it when the transverse clamping plate forces the stack 32 against it. Since it is attached to the plate 64, the movable wall element will move downwardly with the cutting die 63 so as to be moving continually out of the path of the cutting die while performing its clamping function against the surface of the as yet uncut portion of the stack 32. In moving downwardly along the surface of the stack 32, the knife edge 65 of the die 63 cuts chips away, the chips being directed to the rear of the apparatus, out of the way of any of the operating mechanism.

It can be observed from FIG. 4 that the angle of taper of the knife edge 65 is the opposite from that which has conventionally been used in the hollow dies. The knife edge has a surface 163 which faces the stack and is parallel to it. The opposite surface 164 tapers away from the surface 163. In the conventional hollow die, the die surface facing the stack is inclined away from the stack so as to avoid the binding of the cut sheets as they move through the hollow die.

T lze electrical control system The electrical circuit for the motor is a simple one as diagrammatically illustrated in FIG. 26. A two hundred and twenty volt source is connected across the motor 66 which has a starter indicated at having a normally open start button 171 and a normally closed stop button 172 in series therewith. Holding contacts 173 operated by the starter 176 are connected across the start button terminals to hold the circuit in after the starter button is released.

The motor runs continuously. Intermittently it drives the conveyor chain drive sprocket 81 through the chain 88 which is connected to the sprocket 89 on the motor drive shaft.

The motor also drives a sprocket 175 which is connected by a chain 176 to a sprocket 177 fixed to a shaft 178 to which the cam system is attached. The cam system 35 comprises four cam discs (FIGS. 2 and 3) 181), 181, 182, and 183. These discs engage the operating arms on limit switches LS-K, LS-V, IAS-T, and LS-CD respectively.

The limit switches are connected into a circuit illustrated in FIG. 25 to operate the three pneumatic rams 40, 41, and 51 and to operate the clutch and brake 85. That circuit is supplied by a one-hundred and ten volt source which is connected to the operating elements through a seires of switches 187. The rams are actuated -by three solenoids: S, 41S and 51S which are connected to the rams 40, 41 and 51 respectively. The solenoid operating valves are spring return valves which cause the operation of the respective rams toward operative position when the solenoids are energized and which cause the rams to be driven back to the normal rest position when the solenoids are de-energized. Each solenoid is connected in series with its respective operating switches: LS-V, LS-K and LS-T respectively, the solenoid and switches being connected in parallel across the one-hundred and ten volt source. The source is connected to the solenoids through a series connected main switch LS-M which is mounted on the table 30 and is actuated by the stack of paper passing over the operating arm 70 (see FIG. 5).

The voltage source is diagrammatically illustrated as being constantly applied to the clutch and brake. Its application to selectively apply either the brake or the clutch is controlled by a relay which is energized by either a conveyor drive limit switch LS-CD or the conveyor braking switch IS-CB. When the relay is energized, the clutch is engaged and the brake is disengaged. When the relay is de-energized, the reverse occurs. Thus, in its normal position, the circuit to the relay is closed through limit switch LS-CB and the clutch is energized. When the limit switch LS-CB is engaged by the conveyor, it is opened and the clutch is de-energized and the brake is applied. When limit switch LS-CD is closed for a short period, the circuit to the relay is energized causing the clutch to be energized and the conveyor to operate until its lug 46 moves past the limit switch LS-CB whereupon that limit switch will close and hold the clutch energized until it is re-opened .by the next succeeding lug 46 on the conveyor.

Operation The operation of the invention will be described with particular reference to FIGS. ll to 23 wherein the operating clamping and cutting elements are illustrated diagrammatically along side a diagrammatic illustration of the calm and limit switch system. In the even numbered gures, the cam system is shown and for the sake of the illustration, the cam discs are shown in graduated sizes. The limit switch circuit is in the condition illustrated in FIG. 25 except that the switch 187 is closed.

When the apparatus elements are in the condition of FIGS. 11 and 12, one stack is being discharged from the clamping and cutting section and a new stack 32 is being introduced. The conveyor chain 45 is moving, causing the lug 46 to move the stack 32 into the clamping and cutting mechanism. The cam discs 180 to 183 are constantly rotating until the motor is turned off. In passing into the clamping and cutting section, the stack engages arm 70 of the main limit switch LS-M causing the main limit switch to close, thereby connecting the three limit switches with which it is in series for operation. It should be observed that, because of the transverse position of the arm 70, it can only be actuated when a stack of paper is moving through the clamping section and therefore the clamping and cutting elements will not lbe actuated unless there is a stack of paper present on which to work.

After limit switch LS-M has been closed and before a lug 46 on the conveyor has an opportunity to engage the limit switch LS-CB, limit switch LS-T is actuated as illustrated in FIG. 14, that switch `being actuated by its arm dropping radially inwardly of the cam disc 182. The actuation of limit switch LS-T causes the transverse clamping plate to be moved into the path of the incoming stack 32 by means of the actuation of the ram 51. The lug 46 drives the paper into engagement with the ram, the lug applying a clamping pressure to the stack until its springs 98 are almost completely compressed. At that point, another lug 46 on the conveyor trips limit switch LS-CB to de-energize the clutch and apply the brake to the conveyor drive thereby holding the stack clamped between the longitudinal clamp formed by the plate 50 and the lug 46.

Even though the conveyor stops, the cam system 35 continues to rotate clock-wise as illustrated in the drawings, until it reaches the angular position illustrated in FIG. 16. In that position, limit switch LS-V drops radially inwardly to an actuated position causing the vertical clamping ram 40 to be operated. That ram drives the plate 57 downwardly carrying with it the roller 55 which drives the transverse clamping plate 53 into engagement with the side of the stack and which carries the clamping block 59 down into clamping engagement with the top ofthe stack. (See FIG. 15.)

As shown in FIG. 18, the cam system continues to rotate until limit switch LS-K is driven radially outwardly to actuate it, which in turn causes the operation of the ram 41 which drives the cutting die downwardly. As the cutting die moves downwardly, as illustrated in FIG. 17, the back-wall portion 52 moves downwardly out of the path of the cutting die and the chips shaved from the cutting operation drop behind the wall 52 and the rest of the apparatus.

While the cutting die is down, the cam system continues to rotate until limit switch LS-T is opened by the cam 182, moving its operating arm radially outwardly. The reverseal of limit switch LS-T causes a reversal of the actuating air pressure ram 51 thereby withdrawing the clamping plate 50.

The cam system continues to rotate until it obtains the position shown in FIG. 22 in which limit switch LS-K is opened by dropping radially inwardly as permitted by the cam discs 180. The application of the air pressure to the ram 41 is reversed and the cutting die and the wall element 52 are raised, returning them to their normal position as illustrated in FIG. 21.

In the next operation, limit switch LS-V is actuated by its cam 181 driving it radially outwardly. The opening of limit switch LS-V causes a reversal of the direction of air pressure to the ram 40 thereby raising the plate 57 to release the vertical clamping pressure. The withdrawal of the roller from the transverse clamping plate 53 permits compression springs 125 to drive the transverse clamping plate 53 away from its engagement with the side of the stack.

These operations having been performed, the cam 183 operates limit switch LS-CD to operate the conveyor drive as illustrated in FIG. 12. That limit switch LS-CD is held in a closed position for a sucient length of time to permit the lug 46 to clear the limit switch LS-CB which will hold the brake and clutch in a condition of energized clutch and de-energized brake until the next succeeding lug 46 engages the limit switch LS-CB.

The herein described sequence of operations is cyclically performed until no more stacks of paper are conveyed to a position under the cutting die.

I claim:

1. Apparatus for cutting a configuration in at least One surface of a stack of sheets comprising,

a table for supporting a stack of sheets,

means including five clamping elements mounted on said table for clamping said stack on its siX surfaces,

a conveyor for moving stacks into said clamping means,

a cutting die movably mounted above said stack,

means for moving said die through said stack to cut a configuration in at least one surface.

2. Apparatus for cutting a configuration in at least one surface of a stack of sheets comprising,

a table for supporting a stack of sheets,

means including five clamping elements mounted on said table for clamping said stack on its six surfaces,

a conveyor for moving stacks into said clamping means,

said conveyor including an upstanding lug constituting a pusher for said stack and one of said five clamping elements,

a cutting die movably mounted above said stack,

means for moving said die through said stack to cut a configuration in at least one surface.

3. Apparatus for cutting a configuration in at least one surface of a stack of sheets comprising,

a table for supporting a stack of sheets,

means including five clamping elements mounted on said table for clamping said stack on its six surfaces,

a cutting die movably mounted above said stack,

means for moving said die through said stack to cut a configuration in at least one surface,

means for moving one of said clamping elements out of the path of said cutting die as said cutting die passes through said stack.

4. Apparatus for cutting a configuration in at least one surface of a stack of sheets comprising,

a table for supporting a stack of sheets,

a cutting die movably mounted above said stack, means for moving said die through said stack to cut a configuration in at least one surface,

an endless conveyor for moving stacks to a position adjacent said cutting die,

longitudinal clamping means engageable with the downstream end of a stack,

lugs on said conveyor in engagement with the upstream end of said stack, said lugs including a plate supported in part by compression springs for resilient engagement with said stack.

5. Apparatus for cutting a configuration in at least one surface of a stack of sheets comprising,

a table having a surface for supporting a stack of sheets,

a back wall having a surface engaged by said sheets,

means including said table and Wall surface and four clamping elements mounted on said table for clamping said stack on its six surfaces,

a cutting die movably mounted above said stack,

means for moving said die through 'said stack to cut a configuration in at least one surface,

an endless conveyor having a plurality of spaced lugs for moving each of said stacks to a position adjacent said cutting die,

a longitudinal clamping plate transversely movable into the path of a stack to be engaged by a stack and to form a longitudinal clamp with said conveyor lug` 6. Apparatus for cutting a configuration in at least one surface of a stack of sheets comprising,

a table having a surface for supporting a stack of sheets, means including five clamping elements mounted on said table for clamping said stack on its six surfaces, one of said clamping elements being constituted by a back-Wall movably mounted in a position perpendicular to said table surface, a cutting die movably mounted above said stack, means for moving said die parallel to said back-wall thro-ugh said stack to cut a configuration in at least one surface, said wall being movable ahead of said die as said die moves through said stack. 7, Apparatus for cutting a configuration in at least one surface of a stack Of sheets comprising,

a table having a surface inclined approximately to horizontal, a Wall projecting perpendicularly to said table surface g5 to provide a V-cradle for supporting stacks of sheets, means including said table surface, said back-Wall and four additional elements for clamping said stack on its six surfaces, a cutting die movably mounted above said table, 30 means for movin7 said die through said stack to cut a configuration in at least one surface thereof. 8. Apparatus for cutting a configuration in at least on surface of a stack of sheets comprising,

a table having a top surface,

a Wall projecting perpendicularly to said table surface to provide a V-cradle for supporting stacks of sheets, a vertical clamp movable perpendicular to table to engage the top of a stack to be cut, power means for driving said vertical clamp, a transverse clamp movable perpendicular to said wall, and cooperating cam means on respective clamps to effect clamping movement of said transverse clamp upon movement of vertical clamp into engagement with said stack, 4,5 a cutting die movably mounted above said table,

means for moving said die through said stack to cut a configuration in at least one surface thereof.

References Cited bythe Examiner UNITED STATES PATENTS 2,073,320 3/1937 Smith 83-375 3,033,067 5/1962 Thumim 83-206 FOREIGN PATENTS @a 1,173,825 10/1958 France.

311,392 5/1918 Germany. 731,342 ll/1940 Germany. 758,941 5/1952 Germany.

50 WLLIAM S. LAWSON, Primaly Examiner. 

1. APPARATUS FOR CUTTING A CONFIGURATION IN AT LEAST ONE SURFACE OF A STACK OF SHEETS COMPRISING, A TABLE FOR SUPPORTING A STACK OF SHEETS, MEANS INCLUDING FIVE CLAMPING ELEMENTS MOUNTED ON SAID TABLE FOR CLAMPING SAID STACK ON ITS SIX SURFACES, A CONVEYOR FOR MOVING STACKS INTO SAID CLAMPING MEANS, A CUTTING DIE MOVABLY MOUNTED ABOVE SAID STACK, MEANS FOR MOVING SAID DIE THROUGH SAID STACK TO CUT A CONFIGURATION IN AT LEAST ONE SURFACE. 